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<title>Berkeley DB: DbEnv.close</title>
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<h1>DbEnv.close</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public void close(int flags)
    throws DbException;
</pre></h3>
<h1>Description</h1>
<p>The DbEnv.close method closes the Berkeley DB environment, freeing any
allocated resources and closing any underlying subsystems.
<p>Calling DbEnv.close does not imply closing any databases that
were opened in the environment, and all databases opened in the
environment should be closed before the environment is closed.
<p>The <b>flags</b> parameter is currently unused, and must be set to 0.
<p>Where the environment was initialized with the <a href="../api_java/env_open.html#DB_INIT_LOCK">Db.DB_INIT_LOCK</a> flag,
calling DbEnv.close does not release any locks still held by the
closing process, providing functionality for long-lived locks.
<p>Where the environment was initialized with the <a href="../api_java/env_open.html#DB_INIT_MPOOL">Db.DB_INIT_MPOOL</a>
flag, calling DbEnv.close implies calls to <a href="../api_java/memp_fclose.html">DbMpoolFile.close</a> for
any remaining open files in the memory pool that were returned to this
process by calls to <a href="../api_java/memp_fopen.html">DbMpoolFile.open</a>.  It does not imply a call to
<a href="../api_java/memp_fsync.html">DbMpoolFile.sync</a> for those files.
<p>Where the environment was initialized with the <a href="../api_java/env_open.html#DB_INIT_TXN">Db.DB_INIT_TXN</a> flag,
calling DbEnv.close aborts any unresolved transactions.
Applications should not depend on this behavior for transactions
involving Berkeley DB databases; all such transactions should be explicitly
resolved.  The problem with depending on this semantic is that aborting
an unresolved transaction involving database operations requires a
database handle.  Because the database handles should have been closed before
calling DbEnv.close, it will not be possible to abort the
transaction, and recovery will have to be run on the Berkeley DB environment
before further operations are done.
<p>Where log cursors were created using the <a href="../api_java/log_cursor.html">DbEnv.log_cursor</a> method, calling
DbEnv.close does not imply closing those cursors.
<p>In multithreaded applications, only a single thread may call
DbEnv.close.
<p>After DbEnv.close has been called, regardless of its return, the
Berkeley DB environment handle may not be accessed again.
<p>The DbEnv.close method throws an exception that encapsulates a non-zero error value on
failure.
<h1>Errors</h1>
<p>The DbEnv.close method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the DbEnv.close method may fail and
throw a <a href="../api_java/runrec_class.html">DbRunRecoveryException</a>,
in which case all subsequent Berkeley DB calls will fail in the same way.
<h1>Class</h1>
<a href="../api_java/env_class.html">DbEnv</a>
<h1>See Also</h1>
<a href="../api_java/env_list.html">Database Environments and Related Methods</a>
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